Cleo....Tess....Sylvie

So we are ttc for baby number 3. We have gone through a lot of names. First we thought Eleanor and Penelope but we decided that those were too popular and we really don't like the nicknames. Then there was Edith, love the nickname Edie but it sounds so harsh next to Lilla and Vivienne. Then we thought Eloise and Sylvie but we also don't like Eloise's nicknames, it's a bit too frilly and Sylvie sounds too much like Vivi. So now we are thinking Cleo and Tess? Thoughts? We're still loving Sylvie, would it work if there was a sibling between Sylvie and Vivienne to break things up a bit, also as she gets older we think the nn Vivi will phase out.